package common import ( "encoding/binary" "fmt" "math/big" "time" ethCommon "github.com/ethereum/go-ethereum/common" "github.com/hermeznetwork/hermez-node/utils" "github.com/iden3/go-iden3-crypto/babyjub" "github.com/iden3/go-iden3-crypto/poseidon" ) // Nonce represents the nonce value in a uint64, which has the method Bytes that returns a byte array of length 5 (40 bits). type Nonce uint64 // Bytes returns a byte array of length 5 representing the Nonce func (n Nonce) Bytes() ([5]byte, error) { if n >= 1099511627776 { // 2**40bits return [5]byte{}, ErrNonceOverflow } var nonceBytes [8]byte binary.LittleEndian.PutUint64(nonceBytes[:], uint64(n)) var b [5]byte copy(b[:], nonceBytes[:5]) return b, nil } // NonceFromBytes returns Nonce from a [5]byte func NonceFromBytes(b [5]byte) Nonce { var nonceBytes [8]byte copy(nonceBytes[:], b[:5]) nonce := binary.LittleEndian.Uint64(nonceBytes[:]) return Nonce(nonce) } // PoolL2Tx is a struct that represents a L2Tx sent by an account to the coordinator hat is waiting to be forged type PoolL2Tx struct { // Stored in DB: mandatory fileds TxID TxID `meddler:"tx_id"` FromIdx Idx `meddler:"from_idx"` // FromIdx is used by L1Tx/Deposit to indicate the Idx receiver of the L1Tx.LoadAmount (deposit) ToIdx Idx `meddler:"to_idx"` // ToIdx is ignored in L1Tx/Deposit, but used in the L1Tx/DepositAndTransfer ToEthAddr ethCommon.Address `meddler:"to_eth_addr"` ToBJJ *babyjub.PublicKey `meddler:"to_bjj"` // TODO: stop using json, use scanner/valuer TokenID TokenID `meddler:"token_id"` Amount *big.Int `meddler:"amount,bigint"` // TODO: change to float16 Fee FeeSelector `meddler:"fee"` Nonce Nonce `meddler:"nonce"` // effective 40 bits used State PoolL2TxState `meddler:"state"` Signature *babyjub.Signature `meddler:"signature"` // tx signature Timestamp time.Time `meddler:"timestamp,utctime"` // time when added to the tx pool // Stored in DB: optional fileds, may be uninitialized BatchNum BatchNum `meddler:"batch_num,zeroisnull"` // batchNum in which this tx was forged. Presence indicates "forged" state. RqFromIdx Idx `meddler:"rq_from_idx,zeroisnull"` // FromIdx is used by L1Tx/Deposit to indicate the Idx receiver of the L1Tx.LoadAmount (deposit) RqToIdx Idx `meddler:"rq_to_idx,zeroisnull"` // FromIdx is used by L1Tx/Deposit to indicate the Idx receiver of the L1Tx.LoadAmount (deposit) RqToEthAddr ethCommon.Address `meddler:"rq_to_eth_addr"` RqToBJJ *babyjub.PublicKey `meddler:"rq_to_bjj"` // TODO: stop using json, use scanner/valuer RqTokenID TokenID `meddler:"rq_token_id,zeroisnull"` RqAmount *big.Int `meddler:"rq_amount,bigintnull"` // TODO: change to float16 RqFee FeeSelector `meddler:"rq_fee,zeroisnull"` RqNonce uint64 `meddler:"rq_nonce,zeroisnull"` // effective 48 bits used AbsoluteFee float64 `meddler:"absolute_fee,zeroisnull"` AbsoluteFeeUpdate time.Time `meddler:"absolute_fee_update,utctimez"` // Extra metadata, may be uninitialized Type TxType `meddler:"-"` // optional, descrives which kind of tx it's RqTxCompressedData []byte `meddler:"-"` // 253 bits, optional for atomic txs } // TxCompressedData spec: // [ 32 bits ] signatureConstant // 4 bytes: [0:4] // [ 16 bits ] chainId // 2 bytes: [4:6] // [ 48 bits ] fromIdx // 6 bytes: [6:12] // [ 48 bits ] toIdx // 6 bytes: [12:18] // [ 16 bits ] amountFloat16 // 2 bytes: [18:20] // [ 32 bits ] tokenID // 4 bytes: [20:24] // [ 40 bits ] nonce // 5 bytes: [24:29] // [ 8 bits ] userFee // 1 byte: [29:30] // [ 1 bits ] toBjjSign // 1 byte: [30:31] // Total bits compressed data: 241 bits // 31 bytes in *big.Int representation func (tx *PoolL2Tx) TxCompressedData() (*big.Int, error) { // sigconstant sc, ok := new(big.Int).SetString("3322668559", 10) if !ok { return nil, fmt.Errorf("error parsing SignatureConstant") } amountFloat16, err := utils.NewFloat16(tx.Amount) if err != nil { return nil, err } var b [31]byte copy(b[:4], SwapEndianness(sc.Bytes())) copy(b[4:6], []byte{1, 0, 0, 0}) // LittleEndian representation of uint32(1) for Ethereum copy(b[6:12], tx.FromIdx.Bytes()) copy(b[12:18], tx.ToIdx.Bytes()) copy(b[18:20], amountFloat16.Bytes()) copy(b[20:24], tx.TokenID.Bytes()) nonceBytes, err := tx.Nonce.Bytes() if err != nil { return nil, err } copy(b[24:29], nonceBytes[:]) b[29] = byte(tx.Fee) toBjjSign := byte(0) if babyjub.PointCoordSign(tx.ToBJJ.X) { toBjjSign = byte(1) } b[30] = toBjjSign bi := new(big.Int).SetBytes(SwapEndianness(b[:])) return bi, nil } // TxCompressedDataV2 spec: // [ 48 bits ] fromIdx // 6 bytes: [0:6] // [ 48 bits ] toIdx // 6 bytes: [6:12] // [ 16 bits ] amountFloat16 // 2 bytes: [12:14] // [ 32 bits ] tokenID // 4 bytes: [14:18] // [ 40 bits ] nonce // 5 bytes: [18:23] // [ 8 bits ] userFee // 1 byte: [23:24] // [ 1 bits ] toBjjSign // 1 byte: [24:25] // Total bits compressed data: 193 bits // 25 bytes in *big.Int representation func (tx *PoolL2Tx) TxCompressedDataV2() (*big.Int, error) { amountFloat16, err := utils.NewFloat16(tx.Amount) if err != nil { return nil, err } var b [25]byte copy(b[0:6], tx.FromIdx.Bytes()) copy(b[6:12], tx.ToIdx.Bytes()) copy(b[12:14], amountFloat16.Bytes()) copy(b[14:18], tx.TokenID.Bytes()) nonceBytes, err := tx.Nonce.Bytes() if err != nil { return nil, err } copy(b[18:23], nonceBytes[:]) b[23] = byte(tx.Fee) toBjjSign := byte(0) if babyjub.PointCoordSign(tx.ToBJJ.X) { toBjjSign = byte(1) } b[24] = toBjjSign bi := new(big.Int).SetBytes(SwapEndianness(b[:])) return bi, nil } // HashToSign returns the computed Poseidon hash from the *PoolL2Tx that will be signed by the sender. func (tx *PoolL2Tx) HashToSign() (*big.Int, error) { toCompressedData, err := tx.TxCompressedData() if err != nil { return nil, err } toEthAddr := EthAddrToBigInt(tx.ToEthAddr) toBjjAy := tx.ToBJJ.Y rqTxCompressedDataV2, err := tx.TxCompressedDataV2() if err != nil { return nil, err } return poseidon.Hash([]*big.Int{toCompressedData, toEthAddr, toBjjAy, rqTxCompressedDataV2, EthAddrToBigInt(tx.RqToEthAddr), tx.RqToBJJ.Y}) } // VerifySignature returns true if the signature verification is correct for the given PublicKey func (tx *PoolL2Tx) VerifySignature(pk *babyjub.PublicKey) bool { h, err := tx.HashToSign() if err != nil { return false } return pk.VerifyPoseidon(h, tx.Signature) } func (tx *PoolL2Tx) L2Tx() *L2Tx { return &L2Tx{ TxID: tx.TxID, BatchNum: tx.BatchNum, FromIdx: tx.FromIdx, ToIdx: tx.ToIdx, Amount: tx.Amount, Fee: tx.Fee, Nonce: tx.Nonce, Type: tx.Type, } } func (tx *PoolL2Tx) Tx() *Tx { return &Tx{ TxID: tx.TxID, FromIdx: tx.FromIdx, ToIdx: tx.ToIdx, Amount: tx.Amount, Nonce: tx.Nonce, Fee: tx.Fee, Type: tx.Type, } } func PoolL2TxsToL2Txs(txs []*PoolL2Tx) []*L2Tx { var r []*L2Tx for _, tx := range txs { r = append(r, tx.L2Tx()) } return r } // PoolL2TxState is a struct that represents the status of a L2 transaction type PoolL2TxState string const ( // PoolL2TxStatePending represents a valid L2Tx that hasn't started the forging process PoolL2TxStatePending PoolL2TxState = "pend" // PoolL2TxStateForging represents a valid L2Tx that has started the forging process PoolL2TxStateForging PoolL2TxState = "fing" // PoolL2TxStateForged represents a L2Tx that has already been forged PoolL2TxStateForged PoolL2TxState = "fged" // PoolL2TxStateInvalid represents a L2Tx that has been invalidated PoolL2TxStateInvalid PoolL2TxState = "invl" )